David Cameron (left) and Ed Miliband (right) have not faced off one-to-one in a television debate.Reuters

Ed Miliband has once again challenged David Cameron to a head-to-head leaders debate, who he accuses of running scared.

The Labour leader has not faced off with his Conservative rival yet, though the pair took part in one seven-way leaders debate on ITV and another question and answer programme on Channel 4, during which both men were grilled by Jeremy Paxman and a studio audience.

"David, if you think this election is about leadership, then debate me one-on-one," Miliband said during a BBC debate between the five main opposition party leaders.

Cameron has turned down offers of a head-to-head debate with Miliband on the grounds that he believes too many television debates would detract attention, time and resources away from actual campaigning. His critics have accused him of cowardice.

But what do you think? Should David Cameron agree to a one-on-one debate with Miliband?